Burner regulating mechanism



Filed March 14, 1953 2 Sheets-Sheet l v jn x eni'ofi GaoaziBoc/. at I MMay 17, 1938. o. L. BOCK BURNER REGULATING MECHANISM 2 Sheet s-Sheet 2Filed March 14, 1935 06c arZ. Boa/5.

ZV/izws 5 Patented May 17, 1938 PATENT OFFICE BURNER REGULATINGMEOHANISMOscar L. 11ock,'Madison, Wis.

Application March 14,

' 3 Claims.

' open position, and which provides a relief valve to permit abnormalpressures in the furnace to be relieved and escape through the chimney.

A further object is to provide damper regulating means operatively andsynchronously associa'ted with certain partsof the burner equipment anda thermostat, whereby the burner normally controlled by the operation ofthe thermostat will be prevented from operating except when the damperis open.

Numerous other objects and advantages will be apparent throughout theprogress of the following specification.

The accompanying drawings illustrate a selected embodiment of theinventionand the-views therein are as follows:

Fig. 1 is a detail elevation of a furnace or other heating element andembodying the invention, the view showing the relative arrangement ofthe parts diagrammatically.

35 Fig. 2 is a detail vertical sectional view through the burnerregulating mechanism and, showing its association with parts of theburner equipment.

Fig. 3 is a detail end elevation of the damper operating mechanism.

40 Fig. 4 is a detail end elevation of the damper operated switch.

Fig. 5 is a detail sectional view on the line 5--5 of Fig. 3. a

Fig. 6 is a detail sectional view of Fig. 5. 3

Fig. 7 is a view similar to Fig. 6 but showi some of the parts movedfrom initial toward crating position.

Referring to the drawings, I II designates a furnace, boiler or otherheating member which is provided with a burner H, such as an oil burneror other heating element. eludes the oil supply, the blower, and suchother equipment necessary to cause combustion of the fuel. A flue l2leading from the furnace I0 is on the line 8 -6 The burner II in-.

1933, Serial No. 660,685 (01. 236-1) operatively connected to a chimney3 in the usual manner.

A damper I4 is carried by a supporting collar 'or frame l5 which may befastened to the flue l2 as shown in Fig. 1. The damper M has end 5shafts l6 and ll fixed thereto, and these shafts are revolubly mountedin the damper frame l5, Fig. 2. An arm I8 is rigidly connected to theshaft l6 and has a shoulder l9 formed thereon which is adapted to beengaged by a shoulder '10 'on the arm 2| which is freely mounted on theshaft IS. A spring 22 is interposed between the arms I8 and 2| and inengagement therewith to provide a yieldable. connection between thesetwo arms. The arm 2| is pivoted at 23 to a link or connecting arm 24which 'is pivoted at 25 to a connecting arm or crank- 26. The connectingarm or crank 26 is operated by the shaft 21 of a motor 28.

"A thermostat 29 is positioned in a room or the living quarters of thebuilding in which the burn- ,er is located and is provided with contacts30 and 3| connected to the terminals 32 and 33 respectively which leadto the motor 28, Fig. 2. A suitable contacting device, such as a mercurytubeKSfl, is controlled by suitable means operated by the rise and fallof the temperature. When the temperature of the room in which thethermostat is located reaches a predetermined minimum. the mercury tube34 will be moved to the position shown in dotted lines in Fig. 2 andcomplete the circuitbetween the contacts 30 and 3| to operate the motor28. The closing of the contacts 30 and'3l causes the motor to rotate180, the motor being constructed and arranged to rotate only 180, andthen cease. The 180 rotation of the motor 28 will move the crank 180 andcause the members 24 and 2| to rotate the shaft l6 and consequently thedamper 90. at which time the damper will be in open position. 40

A mercury switch arranged in a casing 38, Figs. 2 and 4, is fastened toa bracket support 31 which is fixed to the frame IS. The switch has ashaft which is fixed to thedamper shaft H as indicatedv at 39, .Fig. 2,and ismovable there- 45 with. An arm is mounted on the shaft 38 andcarries a mercury tube 4| having conductors 42 and 43. The conductors l2and 43 are operatively connected to conductors 44 and 45 which lead tothe burner equipment When the mercury tube 4| is in the position shownin Fig. 4, the mercury 46 will be at one end of the tube, but whenthemotor 28 operates to open the damper andnonsequently swing the arm 60by the spring 5| from the position shown in full lines to the positionshown in dotted lines in Fig. 4, the mercury 46 will close the contactbetween the conductors l2 and 43, cause the current to flow through theconductors 44 and 45 and operate the burner equipment II. The burnerwill then operate until sumcient heat has been delivered to cause thethermostat toagain operate and break the con- The parts are soconstructed and arranged I that the position of the damper controls theop- .eration of the heating equipment because when the damper is closedthe burner equipment cannot operate. Therefore, the device completelysafeguards the burner against the possibility of firingwhen the damperis in any but in open .position. If the motor 28 should fail to operate,

no hazard is created because the switch 35 cannot close. If the damperI4 is stuck or corroded tight so that it cannot open, no hazard will becreated as the burner will remain in off position.

A break in either circuit with the damper in closed position will createno hazard. Also, a break in either circuit with the damped open will notcreate a hazard. Current failure at any time will cause a shut-down ofthe equipment regardless of the position of the damper. Due to theyielding connection between the damper l4 and the arm 2|, the damper ispermitted to open against a pressure on its face from within thefurnace. .Therefore, should any abnormal pressure occur against thedamper It, the damper will be allowed to rotate away from the shoulderagainst the tension of the spring 22. When the pressure against thedamper ceases, the spring 22 will be returned to its normal position.The damper herein is pivoted above its normal axial center line.

The burner II is preferably wired to a. separate line but if desired,the burner motor can be fed from a line running from the motor 28 ortaken from the thermostat in which case the thermostat 29 and the switch'35 will be in'series. The breaking of either of these switches willcause the burner to stop before the damper starts to close. Furthermore,the burner will not start un; til both of the switches are closed.

The invention provides a thermostatically controlled driving meansoperating a damper through a yieldable member. The damperopcrates aswitch mechanism which controls the operation of a burner with respectto the position of the damper, and the damper is mounted off center sothat it may be opened against the tension of the spring when there ispressure against the face of the damper. This construction provides forthe necessary lag or lapse of time between the time the thermostatstarts 0 open the damper and the starting of the burner. The burnerstops quickly before the damper closes more than a fraction of itsswing. This is due to the use of an independent switch which has noconnection with the thermostat or damper op erating mechanism.Therefore, the burner is provided with independent timing means andovercomes the objection to conventional burners now on the market whichare so arranged that when the thermostat closes, its circuit starts theburner and the damper opening mechanism at the same time as both of themare connected di- 7 a switch which starts and stops the burner sole- 1ythrough the movement of the damper in the smoke-pipe of flue l2. Whenthe damper is closed, the burner is stopped and when the damper isopened, the burner starts. The thermostatically controlled mechanism 29causes the operation of the damper by opening or closing the samedepending upon the temperature in the room, which temperature governsthe operation of the thermostat. The spring relief and the mounting ofthe damper above its center line permits the damper .to be moved asufiicient distance to overcome abnormal pressures in the furnace. Whenthe temperature in the room reaches a predetermined minimum, thethermostat 29 will operate and cause the motor 28 to open the damper.The movement of the damper will cause the switch to operate to start theburner equipment. However, it is to be noted that the damper will bealmost to its open position before the switch 35 operates to start theburner equipment. When suflicient heat has been generated to againeffect operation of the thermostat 29, the thermostat 29 will cause themotor 28 to operate and swing the damper from open toward closedposition. Slight movement of the damper l4,however, will quickly breakcontact of the switch 35 and cause an interval of time between thestopping of the burner equipment and the complete closing of the damper.Therefore, the pressures and gases in the furnace will be dissipat edbefore the damper completely closes. As the damper closes shortly afterthe shut-off of the burner equipment, the heat in the furnace is keptfor useful heating, purposes instead of being rapidly dissipated throughthe flue.

The switch 35 is provided with adjustable means 50 for setting and/orlimiting the movement of the arm 40, there being a spring 5!, Fig. 2,provided for yieldingly operating the arm 40.

The invention provides new and improved simply constructed, positivelyand eificiently operated means for controlling the stopping and startingof the burner equipment which is controlled by the position of a damper.

Changes may be made in the form, construction, and arrangement of theparts without departing from the spirit of the invention or sacrificingany of its advantages, and the right is hereby reserved to make all suchchanges as 'fairly fall within the scope of the following static controlmeans being operatively connected ,to the damper to selectively move thedamper to open or closed position, a switch connected with the damper,said switch connection being arranged to actuate the switch to closedposition when the damper has opened a predetermined degree and to returnthe switch to open position when the damper has closed a predetermineddegree, said switch being wired to said burner actuating means forcontrol thereof in accordance with the setting of the switch, the damperbeing yieldabie by a predetermined elevated pressure within the furnacetoward open position, and means to permit said yieldable opening of thedamper within limits without closing the switch.

2. A combustion system comprising a furnace,

a burner for the furnace, means to actuate the burner, a flue leadingfrom .the furnace for conveying off the combustion products of theburner, thermostatic control means arranged in operative relationship tothe furnace and operable in accordance with temperature conditionscreated by the furnace, a damper in said flue and operable to open orclosed position, the thermostatic control means being operativelyconnected to the damper to selectively move the damper to open or closedposition, a switch connected with the damper, said switch connectionbeing arranged to actuate the switch to closed position when the damperis opened and to return the switch to open position when the damper isclosed, said switch being connected to said burner for control thereof,said damper being yieldably supported for actuation toward open positionby a predetermined increased pressure within the furnace when the damperhas been selectively actuated to said closed position by the saidthermostat, said switch and damper connection being arranged 'to permitsaid yieldable opening without actuating the switch toclosed position.-

3. A combustion system comprising a furnace, a burner for the furnace,means to actuate the burner, a flue leading from the furnace forconveying off the combustion products of the burner,

thermostatic control means arranged in operative relationship to thefurnace and operable in accordance with temperature conditions createdby the furnace, a damper in said flue and operable to open or closedposition, the thermostatic control means being operatively connected tothe damper to selectively movethe damper to open or closed position, aswitch connected with the damper, said switch connection being arrangedto actuate the switch to closed position when the damper is opened andto return the switch to open position when the damper is closed, saidswitch being connected to said burner for control thereof, the damperbeing yieldable subject to a predetermined elevated pressure within thefurnace toward open position, and means to permit said yieidable openingof the damper within limits without operating the burner.

OSCAR L. BOOK.

